>> difff(fft(in/ 2^8), out/2^4)
max(data0-data1) =  +0.051162 +0.051162i =  +0.0511623 +0.0511623i
min(data0-data1) =  +0.000000 +0.000000i =  +0 +0i
max(data0/data1) = -Inf -Infi
min(data0/data1) = +Inf +Infi
approx separated mean(data0/data1) = +0.874902+ +0.874902i
Energy_data0 = 261888.062500
Energy_diff  = 0.027371
Energy_data0/Energy_diff = 9568163.294833 = 69.808286dB